As death toll rises, WHO warns Ebola could infect 20,000 people

Volunteers prepare to remove the bodies of people who were suspected of contracting Ebola and died in the community in the village of Pendebu, north of Kenema.

The Ebola outbreak in West Africa has killed more than 1,552 people out of 3,069 known cases in four countries and "continues to accelerate", the World Health Organisation (WHO) said adding it could infect more than 20,000 people. The UN health agency said an international effort costing almost half a billion dollars is needed to overcome the outbreak.

The WHO estimates it will take six to nine months to halt the Ebola epidemic in West Africa, while Nigeria said that a doctor involved in treating the Liberian-American who brought the disease to the country had died in Port Harcourt, Africa's largest energy hub, although the cause had yet to be confirmed.

So far 3,069 cases have been reported in the outbreak but the WHO said the actual number in Guinea, Sierra Leone, Liberia and Nigeria could already be two to four times higher.

With a fatality rate of 52 percent, the death toll stood at 1,552 as of August 26. That is nearly as high as the total from all recorded outbreaks since Ebola was discovered in what is now Democratic Republic of Congo in 1976.

"This is not a West Africa issue. This is a global health security issue," Bruce Aylward, the WHO's Assistant Director-General for Polio, Emergencies and Country Collaboration, told reporters in Geneva.

He said tackling the epidemic would cost an estimated $490 million, involving thousands of local staff and 750 international experts. "It is a big operation. We are talking (about) well over 12,000 people operating over multiple geographies and high-risk circumstances. It is an expensive operation," he added.

"More than 40 percent of the total number of cases have occurred within the past 21 days. However, most cases are concentrated in only a few localities," the United Nations health agency said in a statement.

The disease has overwhelmed West Africa's already fragile health infrastructure. Yesterday, the head of the African Development Bank said it was causing enormous damage to the economies of the region.